mat in tn Posted October 30, 2023 Share Posted October 30, 2023 I finally found a bolt-on muffler kit on Rock Auto that was in stock. The project ended up needing some modification, because the old catalytic converter was more than twice the length and 10% wider than the new one I ordered at Oreilly's. The cat mount and cat shield wouldn't even come close to fitting on it, and there was no way I could modify either the shield or the cat to make it fit. I made it all work in the end, and the new exhaust is mounted! A second issue was that I found a large hole in my exhaust manifold. It's a 1.5"x3" rectangle between cylinders 2 and 3. I still need to pass DEQ with this thing, so I plan to just JB Weld a piece of metal on there, go pass DEQ, and then replace the manifold as time allows. Any objections or advice? The noise of the motor and the exhaust getting into my heat/air when the vehicle is stopped is a low priority for me. I also have a question. When I removed section of exhaust pipe from the manifold, I noticed a little valve door inside that diverts exhaust flow away from the tailpipe and sends it somewhere else. It's spring loaded and is adjustable from a little knob on the outside of that section of pipe. What is the purpose of this valve? Where is the exhaust being diverted to? Happy 4th of July! Jack I have been away far too long. anyway I noticed that nobody answered the question. the diverter valve is there to divert exhaust gases (heat) away from the exhaust pipe until it circulates around the base of the intake below the carburetor first in the effort to warm up the intake and fuel air blend until operating temp. there is a thermostatic bimetal coil on one side to close it when cold and a return spring on the other side to pull it open as the coil warms up. these have been known to rust stuck in the closed position on trucks which have been sitting too long. kills power and mileage. Link to comment Share on other sites More sharing options...
wasteland_jack Posted December 23, 2023 Author Share Posted December 23, 2023 I have been away far too long. anyway I noticed that nobody answered the question. the diverter valve is there to divert exhaust gases (heat) away from the exhaust pipe until it circulates around the base of the intake below the carburetor first in the effort to warm up the intake and fuel air blend until operating temp. there is a thermostatic bimetal coil on one side to close it when cold and a return spring on the other side to pull it open as the coil warms up. these have been known to rust stuck in the closed position on trucks which have been sitting too long. kills power and mileage. Merry Cristmas, all! Thanks for the answer to that question @mat in tn! My diverter valve is fortunately not rusted shut. My rear suspension is sagging on the passenger's side, and I believe it is causing uneven wear on a rear tire. I'm looking at replacing the leaf springs and rear shocks. Is there anything I should replace or examine at the same time? Does the group have any favorite brands? A common simultaneous replacement from my research was the sway bar. Another part I plan to change is the timing gears. I don't know what mine looks like, but my timing jumps occasionally. The job also looks fun. I've seen a few videos where people don't pull the engine, but instead just remove the radiator to access the front of the motor. The rest of the tools used by those people for that job are all readily available. Feel free to drop advice for this task if you have it. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 23, 2023 Share Posted December 23, 2023 Merry Cristmas, all! Thanks for the answer to that question @mat in tn! My diverter valve is fortunately not rusted shut. My rear suspension is sagging on the passenger's side, and I believe it is causing uneven wear on a rear tire. I'm looking at replacing the leaf springs and rear shocks. Is there anything I should replace or examine at the same time? Does the group have any favorite brands? A common simultaneous replacement from my research was the sway bar. Another part I plan to change is the timing gears. I don't know what mine looks like, but my timing jumps occasionally. The job also looks fun. I've seen a few videos where people don't pull the engine, but instead just remove the radiator to access the front of the motor. The rest of the tools used by those people for that job are all readily available. Feel free to drop advice for this task if you have it. Definitely check the rear shackle mounts for rot in the pockets and rust jacking against the frame. Closely examine the shock mounts inside the frame and at the axle. I've used Dorman kits to replace these (comes with nuts and bolts to replace the rivets) Dorman got wise and has bigger drain holes. 💡 I've never changed timing gears in situ on a 300 but definitely have with V-8's. I imagine the I-6 is longer? You need a harmonic puller. I can't think of anything else, but hopefully someone who owns one will chime in. Link to comment Share on other sites More sharing options...
mat in tn Posted December 28, 2023 Share Posted December 28, 2023 Definitely check the rear shackle mounts for rot in the pockets and rust jacking against the frame. Closely examine the shock mounts inside the frame and at the axle. I've used Dorman kits to replace these (comes with nuts and bolts to replace the rivets) Dorman got wise and has bigger drain holes. 💡 I've never changed timing gears in situ on a 300 but definitely have with V-8's. I imagine the I-6 is longer? You need a harmonic puller. I can't think of anything else, but hopefully someone who owns one will chime in. I replaced mine back in summer. in the truck after considering it for a few days. honestly i found out that i was wrong and it bugged me:nabble_laughing-25-x-25_orig: I rebuilt the engine twenty years ago and was certain I had installed a steel gear but when I removed the cover and saw a silent gear with twelve teeth missing, I was reminded that my machinist talked me out of steel due to noise. this was the most difficult gear to remove. on the 300 six cyl the gear is a press on fit. best to remove the gear from the cam on a hydraulic press. this is why the cam cover/mounting plate has two bolts and they are accessible through two 1" holes that allow the wrench to go through and the bolt to come out. this requires the removal of the lifters, pushrods. the hydraulic press is to proper install tool also if you are this far. i did install a steel gear this time as I made that decision while waiting to be recovered from the side of I85. yes, it is noisy. however, it has toned down after a bit of Miles. Maybe it's just time to remove the muffler. Link to comment Share on other sites More sharing options...
FuzzFace2 Posted December 28, 2023 Share Posted December 28, 2023 I replaced mine back in summer. in the truck after considering it for a few days. honestly i found out that i was wrong and it bugged me:nabble_laughing-25-x-25_orig: I rebuilt the engine twenty years ago and was certain I had installed a steel gear but when I removed the cover and saw a silent gear with twelve teeth missing, I was reminded that my machinist talked me out of steel due to noise. this was the most difficult gear to remove. on the 300 six cyl the gear is a press on fit. best to remove the gear from the cam on a hydraulic press. this is why the cam cover/mounting plate has two bolts and they are accessible through two 1" holes that allow the wrench to go through and the bolt to come out. this requires the removal of the lifters, pushrods. the hydraulic press is to proper install tool also if you are this far. i did install a steel gear this time as I made that decision while waiting to be recovered from the side of I85. yes, it is noisy. however, it has toned down after a bit of Miles. Maybe it's just time to remove the muffler. Matt I would like to know how can teeth be missing on a 300 timing gear set up? I think I have seen it posted 1 or 2 others also had it happen just dont know why? I had to replace the timing cover gasket, think was last year on New Years Eve, because of a oil leak. At that time I looked over the gears and they looked good so new gasket and no more oil leak. I have seen it posted to get the gear off the cam can be a bear, hope I never have to. Dave ---- Link to comment Share on other sites More sharing options...
mat in tn Posted December 28, 2023 Share Posted December 28, 2023 I replaced mine back in summer. in the truck after considering it for a few days. honestly i found out that i was wrong and it bugged me:nabble_laughing-25-x-25_orig: I rebuilt the engine twenty years ago and was certain I had installed a steel gear but when I removed the cover and saw a silent gear with twelve teeth missing, I was reminded that my machinist talked me out of steel due to noise. this was the most difficult gear to remove. on the 300 six cyl the gear is a press on fit. best to remove the gear from the cam on a hydraulic press. this is why the cam cover/mounting plate has two bolts and they are accessible through two 1" holes that allow the wrench to go through and the bolt to come out. this requires the removal of the lifters, pushrods. the hydraulic press is to proper install tool also if you are this far. i did install a steel gear this time as I made that decision while waiting to be recovered from the side of I85. yes, it is noisy. however, it has toned down after a bit of Miles. Maybe it's just time to remove the muffler. Matt I would like to know how can teeth be missing on a 300 timing gear set up? I think I have seen it posted 1 or 2 others also had it happen just dont know why? I had to replace the timing cover gasket, think was last year on New Years Eve, because of a oil leak. At that time I looked over the gears and they looked good so new gasket and no more oil leak. I have seen it posted to get the gear off the cam can be a bear, hope I never have to. Dave ---- well what ford designed as their "silent gear" is a steel crank drive gear mated with a composite cam driven gear. the composite has a steel core to press onto the camshaft, but it is "set" molded into a fibrous material that is easily mistaken for Kevlar/fiberglass. it is very hard. and very strong yet not near as strong as steel. with mesh helical gears the idea is that the stresses are shared across more than just one tooth at a time. but if one gets weak or fractured it does not carry its load and the following get the added stress. in my case i was at highway speed driving home from work and the engine stuttered, backfired, and shut off without the first clue. we checked for fire thinking coil. then checked for rotor rotation just to be thorough and realized this was not a roadside fix Link to comment Share on other sites More sharing options...
wasteland_jack Posted December 31, 2023 Author Share Posted December 31, 2023 well what ford designed as their "silent gear" is a steel crank drive gear mated with a composite cam driven gear. the composite has a steel core to press onto the camshaft, but it is "set" molded into a fibrous material that is easily mistaken for Kevlar/fiberglass. it is very hard. and very strong yet not near as strong as steel. with mesh helical gears the idea is that the stresses are shared across more than just one tooth at a time. but if one gets weak or fractured it does not carry its load and the following get the added stress. in my case i was at highway speed driving home from work and the engine stuttered, backfired, and shut off without the first clue. we checked for fire thinking coil. then checked for rotor rotation just to be thorough and realized this was not a roadside fix I see cast iron, aluminum, and steel options for timing gears. After reading for an hour, all I see are personal accounts on Ford threads with opinions and old wives tales, but no science stating why one might be better than another. Are these three options essentially equal? Is any of the three a clear winner on this motor? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted December 31, 2023 Share Posted December 31, 2023 I see cast iron, aluminum, and steel options for timing gears. After reading for an hour, all I see are personal accounts on Ford threads with opinions and old wives tales, but no science stating why one might be better than another. Are these three options essentially equal? Is any of the three a clear winner on this motor? Aluminum is bonded to plastic teeth on the cam gear (this is how it came) Steel is used for the crank gear because it has 1/2 the teeth it sees twice the wear. You want to run cast iron against cast iron But this is like distributor gears which also come in steel, iron or composite depending on what your cam billet is made of. Link to comment Share on other sites More sharing options...
wasteland_jack Posted February 4 Author Share Posted February 4 Aluminum is bonded to plastic teeth on the cam gear (this is how it came) Steel is used for the crank gear because it has 1/2 the teeth it sees twice the wear. You want to run cast iron against cast iron But this is like distributor gears which also come in steel, iron or composite depending on what your cam billet is made of. Steel timing gears are on the way, as well as new seals for the pushrod cover, valve cover, and timing cover. Cork seals were suddenly on sale for about $2 a piece on Rock Auto's wholesale closeout. I just pulled off my bed liner. See the dirty/clean pictures below. It doesn't seem too bad for an old truck, but what would be the best way to prevent more corrosion? Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted February 4 Share Posted February 4 Steel timing gears are on the way, as well as new seals for the pushrod cover, valve cover, and timing cover. Cork seals were suddenly on sale for about $2 a piece on Rock Auto's wholesale closeout. I just pulled off my bed liner. See the dirty/clean pictures below. It doesn't seem too bad for an old truck, but what would be the best way to prevent more corrosion? jpg file too large for this antiquated forum software to process. Use the 'big size' button in the 'insert image' drop-down..... Are you putting the liner back in? I would say a phosphoric acid treatment like Kleen-Strip concrete & metal prep or Ospho. It changes the rust (iron oxide) to iron phosphate creating a layer that won't continue to corrode. You can then paint or oil it. Link to comment Share on other sites More sharing options...
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